I remember enjoying this book when I read it a decade ago and rating it a 4*. Unfortunately knocking it down to a 3* in this current re-read. 

The elements I enjoyed included engaging prose, a lot of promising characters and interesting worldbuilding. The elements I did not enjoy were
1. How heavily the plot relied on deux ex machina for further progression and resolution. Rialla, Ren and Laeth seemed like interesting, likable characters; they were also remarkably incompetent with bad strategic judgement considering their implied experiences as mercenaries and spies. There was no real need for Rialla to do a lot of the things she did e.g. give a public dance performance that drew attention, when she tasked with being quiet and unnoticed in the background listening to secrets. Rialla even had difficulty reading the script of the people that she wanted to spy on; she was incredibly lucky that she didn't end up sabotaging her own cause. Laeth made for a very poor spy, considering he just

left without asking Rialla what her plan was - it was a very flimsy plan (find a dagger that may have been thrown away for all they knew) that only became better after discussion

and also a very poor friend, considering that he didn't even bother to

go back to help her when he showed up near the end of the story

. As the spymaster, Ren was mostly there to provide exposition and no actual support. It was up to Tris, a random healer who had mostly lived in a secluded enclave and then a small village, to do most of the work of spying, communicating and rescuing, and he did it unbelievably well. 
2. The lack of well developed female characters aside from Rialla - this does not feel like a book that would pass the Bechdel test.